This is an application for a new NICHD Population Research Center Core Support Grant to the Population Issues Research Center (PIRC) at The Pennsylvania State University. Established in 1972, the PIRC is an interdisciplinary center that encourages, organizes, and supports research and training in population. In the mid-1980s, a coordinated and concerted University effort resulted in dramatic improvements in population research and training at Penn State, including the assembling of a well-trained, productive faculty with a demographic research agenda appropriate for the 1990s; achieving a strong portfolio of qualifying demographic research grants; and putting in place the requisite core demographic research support services. Demographic research at Penn State typically involves the statistical analysis and modelling of the causes or consequences of demographic behaviors of individuals in populations. The major research program themes in the 1990s include (1) dramatic transformations of family structures, and their consequences for the aging of populations, adequacy of employment, family poverty, racial and ethnic inequality, and intergenerational relations, (2) interrelation of fertility and mortality behaviors with biological processes and population genetics, and (3) development of improved methods for data collection and the analysis of demographic behavior and change. Attention to the cultural and social structural contexts of behaviors, and to their place in the individual life course, distinguishes this research. The PIRC consists of 27 Associates form 7 departments and 4 colleges. From 1986-1990 PIRC Associates were awarded 32 externally supported research grants and produced 296 scholarly publications. Core support is requested for 4 PHS grants, 6 NSF grants, 2 private foundation grants, and 1 grant from other sources in population already in place for July 1, 1991. If funded, 2 pending and 4 planned PHS grants and 4 other grants also would use core support. The PIRC coordinates a dual- title degree in demography with Hewlett Foundation support and an NIA post-doctoral training program. Funding requested for the PIRC's Administrative, Statistical, Information, and Computer cores will improve the productivity of demographic research by maintaining essential research units staffed by knowledgeable and experienced professionals, enabling researchers to use their existing research grants more effectively, and providing research services that will improve the quality of the research produced.